Measurement of Compton scattering on bound electrons by the coincidence method

A review of results of the new method for measuring the Compton scattering on bound electrons in germanium, introduced by the presented authors, is given. It is based on the application of two detectors that operate in the coincidence mode. One detector is used as the scatterer and the other as the detector of scattered radiation. Two conditions, simultaneity of pulses from the two detectors and constant energy sum, result in very clean spectra in broad energy regions. Normalization of the Compton spectra to the Ge K X-ray escape peaks, which are measured simultaneously with the Compton spectrum, gives reliable double-differential Compton-scattering cross sections on an absolute scale. Several versions of the impulse approximation are compared to the cross sections obtained by the present method for incident photon energies in the range from 60 to 105 keV. The non-relativistic impulse approximation gives the best agreement to the experimental data. We point out the suitability of the new method for an investigation of the incoherent scattering function at small photon momentum transfer.